> The only solution will be regulation.
What's the problem exactly, and how would regulation work to address it?
I feel that people gravely misunderstand capital, interest rate, and so on. Capital accumulation is not the same as expanding the money supply (so taking out a loan) - even if both are somehow denominated in USD. If we have too much financial capital - as you pointed out, chasing returns - that just means its real value depreciates compared to other things. (Eg. capital goods, labor, return generating assets, etc. - That's why we see asset bubbles, and investment in a lot of ventures, that then pays huge salaries.)
But it doesn't matter how much money chases how little, the important thing is the real growth, aggregate demand (total compensation), technological change (productivity), and so on.
There's back-pressure (falling profits, slowing growth, recession, depression, shrinking economy, rising unemployment, a vicious cycle), but also there's always a place for financial capital to go. Namely there are always new ideas to try, there are always things to invest in.
For example, there are always more riskier and more longer term investments, such as education (lending people money to retrain and switch to a higher paying job - a bit like student loans, but a lot more like coding bootcamps). Infrastructure (public transport, energy, housing), and so on.
Profit (real capital) comes from economic surplus, and that comes from technological change (economies of scale, efficiency, etc). And fundamentally it seems advanced economies are very resistant to switch to more efficient forms. ( http://www.vitalsigns.mtc.ca.gov/time-spent-congestion --- and it took a pandemic to try to make home office really viable; see also how much money people spend on healthcare, yet how inefficient it is)
Without real economic surplus a bigger money supply is just inflation. (That's why some people freak out when they see central banks doing quantitative easing, but they forget that central banks look at inflation, and they do QE to keep inflation above 0.)
So eventually, either we invest in big changes to go up the efficiency ladder, stagnate, or worst case the promised new projects don't deliver (because there was not enough aggregate demand to subscribe/buy/rent/use the new shiny thing, or it was not green enough, so it was not a good market fit), eventually the financial sector starts to run out of equity to risk, and we fall into the debt trap that caused Japan's lost decade.
(And that's why central banks all around the world are able to just foot the bill, because it doesn't cause inflation as long as that money is basically just gets rolled over into new loans/bonds/etc. most of it goes nowhere.)